Hi @samskiter, AFAIAC the experts on Samsung comms are @Topaz and @toadhall. I merely use F1/F2 as a layman to monitor the Outdoor and Indoor Unit variables using SNET-Pro (which I think is really good even with its flaws). Never investigated F3/F4 so cannot comment, but if you want to try SNET have a look at Samsung ASHPs: Customising Your SNET-Pro2 Display .